It is awesome! I've been in Shenzhen with my startup for a year now and its great.., I want to stay here forever. Apart from the slow internet through the VPN, weird but interesting food and the language barrier, its a very exciting and prosperous country to be in. Foreigners here are treated equally and sometimes treated way better than they deserve!!

Regarding jobs, there are plenty, but it depends which province/city you want to be in. Maybe not as highly paid as the US but there are definitely a lot of cool, innovative, new and weird ideas and concepts that you won't see anywhere in the world! I ask my Chinese friends what's the latest cool things you can do with your phone and they always have these weird apps that maybe in 5 years facebook or youtube will have.

For US citizens its pretty easy to get a visa, apart from the invitation letter crap, you get like a 10 year multi-entry. Us europeans have a harder time to get a 1 year one but not that bad in general :)

It is a bit of a shock the first time you come here and sometimes 2-4 weeks might not be enough to love this place, but after a while you develop a sort of stockholmy syndrome and all is good!

Hope it helps!